essential 9 Associations

indispensable necessary (similar term)

gratuitous 10 Associations

needless uncalled-for unnecessary (similar term) unneeded (similar term)

incumbent 9 Associations

necessary (similar term)

indispensable 13 Associations

essential necessary (similar term)

inessential 11 Associations

unnecessary (similar term) unneeded (similar term)

inevitable 10 Associations

fatal (similar term) fateful (similar term) ineluctable (similar term) inescapable (similar term) unavoidable (similar term) necessary (similar term) evitable (antonym)

needed 6 Associations

needful required requisite necessary (similar term)

needful 7 Associations

needed required requisite necessary (similar term)

needless 8 Associations

gratuitous uncalled-for unnecessary (similar term) unneeded (similar term)

obligatory 10 Associations

necessary (similar term)

required 8 Associations

needed needful requisite necessary (similar term)

requisite 9 Associations

needed needful required necessary (similar term)

spare 5 Associations

unnecessary (similar term) unneeded (similar term)

uncalled-for 12 Associations

gratuitous needless unnecessary (similar term) unneeded (similar term)